一头栽进 yītóuzāijìn to plunge into Definitions Defs Origin Strokes Stroke Words Sentences Sents 一头 一頭 yītóu headlong Plunging forward or downward with the head leading; doing something suddenly or directly.栽 zāi to fall to stumble; to fall headfirst; to tumble down进 進 jìn particle [into] Used after a verb to show movement from the outside to the inside.